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\begin{equation*}=\frac{F'(P_2\!<\!P\!<\!P_3)-2F'(P_1\!<\!P\!<\!P_2)+F'(P_0\!<\!P\!<\!P_1)}{(P_1-P_0)^2},\,\!\end{equation*}
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